I had been checking Craigslist ads for about a year, looking for a decently priced All Wheel Drive car, preferably a tiny Subaru wagon. I was shocked how much money people wanted for a worn-out high-mileage AWD car. I mentioned this fact to a co-worker, who said that he was about to put his daughter's car up for sale.
The car my co-worker was selling wasn't a wagon, but a sedan and I'm OK with that given the price. It's a nice little Subaru with AWD, and it gets about 26 mpg.
That is 10 mpg better than my truck. With the typical ~10% price spread between gasoline and diesel, I estimate the savings at about $400/yr in fuel cost. Additionally since it will take only 5 quarts of oil per change-out, there's some service savings. Tires will be cheaper to replace, etc etc.
Insuring this car only cost an extra $40 annually, becuase it replaced the truck as my primary commuter. It came with a set of studded winter tires, and also a set of summer tires with custom rims. It even has a nice stereo system!
I'm not sure why it has a wing on the trunk. It's certainly not a Formula 1 car...
I keep it parked indoors at work to avoid having to scrape ice off the glass in the morning. Also it's quite a bit warmer inside when it's time to go home...
Most importantly, it has great traction, and handles quite well on ice and snow.